For years , China has talked about promoting `` green growth . '' But this probably is n't what they had in mind .

For the seventh year in a row , monstrous quantities of green algae known as enteromorpha prolifera have sprouted in the coastal waters near Qingdao , China . But this year 's growth , covering 28,900 square kilometers -LRB- 11,158 square miles -RRB- , is the biggest outbreak ever recorded , state-run news agency Xinhua reported . The previous record was 13,000 square kilometers -LRB- 5019 square miles -RRB- in 2008 .

Swimmers and beachgoers were pictured frolicking among the stringy piles of slime , while bulldozers attempted to scoop it away .

Chinese officials have blamed past algae outbreaks on unusually warm seas . Dr. Christopher Bolch , an algae expert at the University of Tasmania , says the explanation does n't hold water .

`` You may get faster growth rates with higher temperatures , but you ca n't get such large amounts of biomass without access to nutrients , '' he explained .

According to Bolch , massive algae blooms feed off of high levels of nitrites and phosphates in the water , which typically comes from agricultural waste , industrial pollution , or human sewage from highly populated areas .

Enteromorpha is `` fairly benign , '' said Bolch , but can harm marine ecosystems . Algae blocks sunlight from reaching aquatic life , reduces oxygen levels , and emits bacteria when the algae dies and rots .

Similar but more dangerous types of aquatic growths , such as phytobacteria or dinoflagellates , can produce harmful toxins and posion people . `` They should consider themselves quite lucky that it 's not one of those , '' said Bolch .

Chinese state media reported that the seaweed began proliferating on June 5 , and that local governments had `` taken measures '' to minimize the impact to marine ecosystems . Officials reported that they had removed around 7,335 tons of algae .

Bolch said enteromorpha typically does not cause health problems in humans , but `` large concentrations of anything can be problematic . ''

There could be a risk of skin inflammation , said Bolch . `` If you were stupid enough to go in , I would n't go in naked . ''

In 2012 : Melting Arctic ` blooms ' with algae

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Coastal waters near Qingdao covered with 28,900 sq km of green algae

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Largest outbreak seen by local officials , doubling previous record in 2008

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Scientist says algae is caused by pollution and sewage in water

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Algae ` generally not harmful ' to humans , but scientist urges caution